Waterfall charts are often used by business professionals to show the cumulative effects of changes to an initial value. Typically, a waterfall chart is made up of multiple columns appears somewhat like a bar graph. Generally, the first column is an initial value, the last column is a cumulative total, and the intermediate columns are change columns. Each change column can be either positive or negative and is dimensioned such that one edge is at the same vertical height as the current cumulative “total” and another, opposite edge is above (for positive change columns) or below (for negative change columns) the first edge by a vertical dimension that is proportional to the degree of change that has occurred. The visual effect of change columns is that they appear to “float” relative to the first column and final column. Change columns are generally color coded to indicate whether the change is positive or negative.
Typically, to create a waterfall chart, professionals start with a regular spreadsheet program and use a series of complicated formulas. Furthermore, such professionals often find themselves creating the floating change columns by stacking visible columns on top of invisible columns.